A gunman identified by Bosnian news reports as a radical Islamist fired an automatic rifle at the American Embassy in downtown Sarajevo on Friday, wounding a guard and paralyzing the city during the afternoon rush hour before a police SWAT team wounded and arrested him.

Black-clad police officers in Sarajevo, the capital of Bosnia-Herzegovina, quickly sealed off the area around the embassy around 3 p.m. local time, as the bearded gunman, wearing a long brown camouflage coat, could be seen strolling the street and brandishing his weapon. A single shot from a police sharpshooter felled him less than an hour later.

The gunman was taken into custody and hospitalized. His motives were not clear. Bosnian leaders expressed shock at the episode, highly unusual for placid Sarajevo, which bears little resemblance to the besieged wartime city that it was during the 1992-1995 Balkans conflict between Croats, Muslims and Serbs.

Some officials called the gunman a terrorist, left open the possibility that he had accomplices and assured American diplomatic officials that they were investigating.

“The American government and people have supported us in the most difficult moments of our history, and nobody has the right to endanger the friendly relations between our two countries,” said Bakir Izetbegovic, one of Bosnia's three presidents.

Mark Toner, a State Department spokesman in Washington, said in a statement that no embassy employees were wounded by the gunman and that the local law enforcement authorities were prosecuting the attack. The building, in the heart of downtown Sarajevo, had been placed on
"lockdown status," meaning nobody could enter or leave, until the assailant was apprehended and the area was declared safe.

"He was walking back and forth in front of the embassy for quite some time," said Srecko Latal, the Bosnia analyst for the International Crisis Group, a political consulting firm, who was attending a meeting a few blocks away. "The whole town went into a complete traffic jam."

Sources said one city police office assigned to guard the embassy had been hit in the arm by the gunman. It was unclear how many shots the gunman had fired.

Dnevni Avaz, the country's leading newspaper, identified the gunman as Mevlid Jasarevic, aged 23 or 24, from Novi Pazar in southwest Serbia. Itquoted Serbian Interior Ministry officials as saying he was a follower of Wahhabism, a strict and highly conservative branch of Islam dominant in Saudi Arabia. The newspaper also said he had a police record, including an arrest last November for carrying a large knife outside a meeting of foreign ambassadors in Novi Pazar.